The present invention relates to video graphics systems, and more particularly to color correction of isolated objects in video graphics systems such as video paint and animation systems.
Color correction systems have evolved with the desire to convert motion picture films into video signals which may be stored on video tape for subsequent television broadcasting using a "film chain." The color correction is desired so that the colors on a television monitor appear to be the same as those in the original color motion picture film, or so that black and white motion picture films may be colorized for home television viewing. There are color correction systems that provide not only for scene-by-scene color correction, but also for objects within a scene. Such object color correction systems store a video frame of data from a video tape in a "still" store. A physical area within the video frame is defined which encompasses the object to be color corrected. An operator manually adjusts hue, saturation and/or luminance to define a region in color space which encompasses the object, the region being defined by observing the video monitor to see when either the object or the background surrounding the object achieves a uniform grey color. Once the region is defined and set, the operator can manually adjust hue, saturation and luminance and only those objects which fall within the defined physical area and the defined color region are affected. Once the color of the object is corrected, the new scene is transferred to an output video tape.
In computerized video manipulation systems such as video paint and animation systems there also exists a desire to provide color correction, or more appropriately color altering, of objects to achieve desired special effects.